Techniques for clearing jams in staplers have included arrangements for spring mounting of the sheath to allow the sheath to be displaced to accomplish unjamming (U.S. Pat. No. 4,570,841). Another technique has included a crank arrangement to accomplish unjamming (U.S. Pat. No. 4,913,332). Compensating spring and head post mounting of staple blade units are old (U.S. Pat. No. 4,720,033).
None of these arrangements has been satisfactory from both operational and cost standpoints.